The UCLA Virology Laboratory has served as a core for the UCLA ACTG since 1987. All the protocols that require viral culture and p24 antigen have been assessed in the Virology Laboratory, and the laboratory has maintained high standards in Quality Assessment programs of the ACTG. We expect to maintain the previous high standards of performance, and in combination with the Virology Developmental Research component (Part C.3), continue to be capable of rapidly assimilating new technologies in HIV virologic diagnostic assessment.